输入管理学习笔记

#include <config.h>
#include <input_manager.h>
#include <string.h>

static PT_InputOpr g_ptInputOprHead;
static T_InputEvent g_tInputEvent;

static pthread_mutex_t g_tMutex  = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t  g_tConVar = PTHREAD_COND_INITIALIZER;

int RegisterInputOpr(PT_InputOpr ptInputOpr)//加入链表 
{
	PT_InputOpr ptTmp;

	if (!g_ptInputOprHead)
	{
		g_ptInputOprHead   = ptInputOpr;
		ptInputOpr->ptNext = NULL;
	}
	else
	{
		ptTmp = g_ptInputOprHead;
		while (ptTmp->ptNext)
		{
			ptTmp = ptTmp->ptNext;
		}
		ptTmp->ptNext	  = ptInputOpr;
		ptInputOpr->ptNext = NULL;
	}

	return 0;
}


void ShowInputOpr(void)
{
	int i = 0;
	PT_InputOpr ptTmp = g_ptInputOprHead;

	while (ptTmp)
	{
		printf("%02d %s\n", i++, ptTmp->name);
		ptTmp = ptTmp->ptNext;
	}
}

static void *InputEventTreadFunction(void *pVoid)
{
	T_InputEvent tInputEvent;
	
	/* 定义函数指针 */
	int (*GetInputEvent)(PT_InputEvent ptInputEvent);
	GetInputEvent = (int (*)(PT_InputEvent))pVoid;

	while (1)
	{
		if(0 == GetInputEvent(&tInputEvent))
		{
			/* 唤醒主线程, 把tInputEvent的值赋给一个全局变量 */
			/* 访问临界资源前，先获得互斥量 */
			pthread_mutex_lock(&g_tMutex);
			g_tInputEvent = tInputEvent;

			/*  唤醒主线程 */
			pthread_cond_signal(&g_tConVar);

			/* 释放互斥量 */
			pthread_mutex_unlock(&g_tMutex);
		}
	}

	return NULL;
}

int AllInputDevicesInit(void)
{
	PT_InputOpr ptTmp = g_ptInputOprHead;
	int iError = -1;

	while (ptTmp)
	{
		if (0 == ptTmp->DeviceInit())
		{
			/* 创建子线程 */
			pthread_create(&ptTmp->tTreadID, NULL, InputEventTreadFunction, ptTmp->GetInputEvent);			
			iError = 0;
		}
		ptTmp = ptTmp->ptNext;
	}
	return iError;
}

int GetInputEvent(PT_InputEvent ptInputEvent)
{
	/* 休眠 */
	pthread_mutex_lock(&g_tMutex);
	pthread_cond_wait(&g_tConVar, &g_tMutex);//	休眠会把锁给释放了 ，到唤醒再把锁给获得 

	/* 被唤醒后,返回数据 */
	*ptInputEvent = g_tInputEvent;
	pthread_mutex_unlock(&g_tMutex);//把锁给释放了
	return 0;	
}

int InputInit(void)
{
	int iError;
	iError = StdinInit();//初始化标准化输入输出 
	iError |= TouchScreenInit();//初始化触摸屏 
	return iError;
}